Hieracium


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Related to Hieracium: Hieracium aurantiacum

Hieracium

 

(hawkweed), a genus of perennial pubescent herbs of the family Compositae. The leaves are entire or deeply toothed; the basal ones are usually in rosettes. The bisexual flowers are ligulate and usually yellow. They are in heads, which are solitary or gathered into a common inflorescence. The fruit is an achene. Many species reproduce by means of apomixis.

There are about 1,000 species (or 15,000 “small” species), distributed in the cold and temperate belts, primarily in the northern hemisphere. The plants also occur on tropical mountains. The USSR has about 700 species. The most common are H. pilosella and Ft. umbellatum. The former grows in meadows, in timber-felling areas, and along roads. H. umbellatum occurs in pine groves, in dry and floodplain meadows, on long-fallow land, and in fallow fields. Some species are cultivated as ornamentals.

REFERENCE

Iuksip, A. Ia. “Rod Hieracium L.—Iastrebinka.” In Flora SSSR, vol. 30. Moscow-Leningrad, 1960.

T. V. EGOROVA

References in periodicals archive ?
Between the least degraded plot (D3) and the most degraded plot (Dl), the important shifts in ground cover were an increase in Hieracium and bare ground from 75% to 95%, and the complete disappearance of Festuca novae-zelandiae (fescue tussock).
Cipriotti PA, Rauher RB, Collantes MB, Braun K, Escartin C (2010) Hieracium pilosilla invasion in the Tierra del Fuego steppe, Southern Patagonia.
4) Tan solo nos hemos permitido incluir el taxon Hieracium pilosella, ambiguo y muy generico, que bien podria implicar desdoblamientos.
Mortier (1998) "Effect of extracts of Orthosiphon stamineus Benth, Hieracium pilosella L.
This revealed the need to treat Hieracium as an important part of the wider, more complex set of difficulties facing sustainable pastoral management in the high country of New Zealand.
McIntosh and Allen (1993) found that pH was significantly lower and organic C values were significantly higher within Hieracium patches than in the adjacent soil, but found no significant difference in total N.
Another daisy with a similar growth habit called Hieracium pilosella has recently expanded its range in New Zealand.
1998) demonstrated that the alien weed Hieracium lepidulum invaded the more fertile microsites in mountain beech forests in New Zealand.
Mendel attempted to verify his results with peas by doing similar experiments with Hieracium (a genus of common European weed), but without great success.
As for the mechanism of MSI1, Quantitative RT-PCR analysis in ovaries of sexual and apomictic Hieracium have suggested that while an increase in HMSI1 is required for autonomous seed development, a decrease seems to precede sexual seed formation (Julio et al.
Achillea moschata, Seeds sown in Stocklin and Baumler Hieracium autumn only (1996) staticifolium, germinated in the Oxyria digyna and spring suggesting Rumex scutatus cold stratification is required for germination in these species.
Hawkweed ydi'r enw Saesneg arnyn nhw a Hieracium ydi'r enw gwyddonol.